We did not go by D-Unit either. Back in pre-9/11 days, it was known as Bomber's Row, because Unabomber Ted Kaczynski was there, alongside Yousef and Oklahoma City bomber Timothy McVeigh. One former officer described the scene in the recreation yard as a "recipe club" where the bombers could trade tips and compare their political views.

These days on D-Unit, it is mostly the second-string terrorists, the ones not considered dangerous enough to rate SAMs. Kaczynski is still there but perhaps more interesting is Olympic Park bomber Rudolph who seems -- from letters written to a Colorado Springs newspaper-- to have taken on the mantle of a prison rights advocate. He's also become fairly fluent in Arabic, getting shouted lessons from some of the other D-Unit residents.

They put Robert Hansen in Supermax? Dude was nonviolent. Putting a spy in there with mass murderers is a low blow from your TTT Yankee security establishment. Max sentence for that shit in Russia is 20 years and not freakin Supermax.

They were workout buddies who had little in common — except for infamous reputations and a skill with explosives.

But housed in neighboring cells on the same secluded wing at the United States Penitentiary Administrative Maximum Facility (ADX) in Florence, Colo., Ted Kaczynski, the Unabomber, struck up an odd friendship with two other notorious terrorists of the 1990s: Oklahoma City bomber Timothy McVeigh and Ramzi Yousef, who planted a bomb in the World Trade Center in 1993 that killed six people, a precursor to the 9/11 attacks.

Locked in their tiny cells 23 hours a day, the three at one point shared the same recreation time. Outdoors, the environment was bleak: an all-concrete yard so deeply recessed that some former prisoners have likened it to standing in an empty swimming pool. But inmates were escorted to individual wire-mesh cages — about 12 by 18 feet, Kaczynski estimated — where they could speak to each other under the watch of guards.

In his early months in prison, Kaczynski became close enough to McVeigh and Yousef that they shared books and talked religion and politics. He even came to know their birthdays, according to letters he wrote about them to others.

“You may be interested to know that your birthday, April 27, is the same as that of Ramzi Yousef, the alleged ‘mastermind’ of the World Trade Center bombing,” Kaczynski wrote to a pen pal in 1999, according to a letter on file at his archive of personal papers at the University of Michigan Library. “I mentioned this to Ramzi, and he wants me to tell you that since your birthday is the same as his, you and he must have similar personalities. … He may have some degree of belief in astrology.”

Known as the “Alcatraz of the Rockies,” ADX is considered to be America’s toughest prison, where the nation’s most dangerous criminals are locked away and meant to be forgotten. But for Kaczynski, who had lived as a hermit for more than 20 years in his remote cabin in the backwoods of Montana, prison was, in many ways, a social awakening. For the first time he had regular, daily contact with other people, even though it was largely with prisoners who had committed equally horrible crimes.

Kaczynski’s letters offer an unprecedented glimpse into what life is like inside ADX, a so-called supermax prison that has been widely criticized for its use of solitary confinement. Kaczynski arrived there in May 1998, shortly after he was given eight life sentences without parole for his 17-year bombing spree, which killed three and left dozens injured. According to his personal papers, Kaczynski so detested the idea of spending the rest of his life in prison that he actually wanted the death penalty.

Though he longed for freedom and mourned the loss of his beloved Montana, Kaczynski admitted to pen pals that ADX wasn’t so terrible as far as prisons went — though he might have been better equipped than most for the lonely existence of a small, enclosed space. (His 12-by-7-foot jail cell is not much smaller than his 12-by-10-foot cabin, which didn’t have running water or electricity.)

“I consider myself to be in a (relatively) fortunate situation here,” Kaczynski wrote in a February 2000 letter. “As correctional institutions go, this place is well-administered. It’s clean, the food is good, and it’s quiet, so that I can sleep, think and write (usually) without being distracted by a lot of banging and shouting.”

The prisoners on his cell block, he added, “are easy to get along with.” He had particular praise for Yousef and McVeigh, whom he described in another letter as “very intelligent … friendly and considerate of others.” “Actually,” Kaczynski told another pen pal, “the people I am acquainted with in this range of cells … are nicer than the majority of people I’ve known on the outside.”

In July 1999, McVeigh was moved to federal death row in Terre Haute, Ind., and though prison rules blocked him from exchanging letters with Kaczynski, they kept up their friendship. Through a journalist at the Buffalo News, McVeigh sent Kaczynski a copy of “Into the Wild,” writer Jon Krakauer’s account of a young man’s hike into the Alaskan wilderness. (Kaczynski, who is particular about his books, liked it.) Meanwhile, the Unabomber asked his pen pals to send McVeigh magazines and articles, including a subscription to Green Anarchy magazine.